Building unit for scaffolding or a trestle

ABSTRACT

A building unit for scaffolding or a trestle is formed as a hollow rectangular box of plastics material which is twice as long as it is wide. The unit has a closed horizontal top in which apertures are formed at the corners of the unit and midway along its length at the sides of the unit. The top is sufficiently strong to provide a support platform for personnel. Pegs aligned with the apertures project below the bottom of the unit for engagement in the apertures in one or more other such units to provide proper horizontal orientation and interconnection between the units. By suitably superimposing two or more of the units in this way, scaffolding or a support for a trestle may be readily assembled.

United States Patent 1191 [H1 3,881,571

Moulton May 6, 1975 1 BUILDING UNIT FOR SCAFFOLDING OR A Primary ExaminerReinaldo P. Machado TRESTLE Attorney, Agent, or FirmMcGlew and Tuttle [76] inventor: Michael Maldwyn Moulton, Pawteg Road, Aberaeron, England 57 ABSTRACT [22] Filed: Oct. 19, 1973 Appl. No.: 408,113

A building unit for scaffolding or a trestle is formed as a hollow rectangular box of plastics material which is twice as long as it is wide. The unit has a closed horizontal top in which apertures are formed at the corners of the unit and midway along its length at the sides of the unit. The top is sufficiently strong to provide a support platform for personnel. Pegs aligned with the apertures project below the bottom of the unit for engagement in the apertures in one or more other such units to provide proper horizontal orientation and interconnection between the units. By suitably superimposing two or more of the units in this way, scaffolding or a support for a trestle may be readily assembled.

6 Claims, 3 Drawing Figures FHENTEDHAY SIQYS SHEET 10F 2 MENTEEMY 6i9?5 sum 2 OF 2 BUILDING UNIT FOR SCAFFOLDING OR A TRESTLE FIELD AND BACKGROUND OF THE INVENTION This invention relates to a building unit for scaffolding or a trestle.

Hitherto scaffolding and trestles have been formed of tubular or solid members of metal or wood assembled to form a lattice-like or similar construction. Planks supported by one or more of these assemblies provide the necessary platforms for personnel.

In the case of scaffolding such an arrangement is liable to be expensive to erect and dismantle because of the large number of individual items involved; on the other hand, for trestles, where dismantling is not usually possible, such an arrangement is liable to be bulky. In either case the constituent members, if tubular, are likely to be made of steel for reasons of economy and therefore are liable to rust and are relatively heavy.

SUMMARY OF THE INVENTION The present invention seeks to provide a unit which, by assembling together two or more such units, enables a scaffold or trestle to be quickly erected and dismantled and which is relatively robust, light, compact and long lasting.

According to the invention there is provided a building unit, for scaffolding or a trestle, in the form of a hollow box having a top and a bottom, one of which is provided with apertures and the other of which has vertical projections extending therefrom for engagement in the apertures of one or more other such units to locate the units in horizontal relation, at least the projections being all located around the sides of the unit, the top being arranged to provide a support platform.

For an understanding of the principles of the invention, reference is made to the following description of typical embodiments thereof as illustrated in the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS In the accompanying drawings:

FIG. I shows a scaffolding or trestle unit embodying the invention when partly cut away to show its interior;

FIG. 2 is an exploded view of part of a scaffolding formed from a plurality of the units of FIG. I; and

FIG. 3 illustrates a modification of the unit.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Refering now to FIG. I, a scaffolding or trestle unit 9 embodying the invention is in the form of an openbottomed. hollow rectangular box which is twice as long as it is wide. The side walls I of the unit are of sheet material as is the unit top 11. Gussets 12 extend between the longer side walls and the top ll so as to strengthen the top II against downward loading.

Formed in the top I l are six apertures of which four, designated 13, are located at the unit corners immediately inside the walls 10, and the fifth and sixth, designated 14, are located midway along the length of the unit in longitudinal alignment with the apertures I3.

The apertures l3 are generally square. The apertures 14 are of the same dimension as the apertures I3 across the width of the unit 9, but along the unit their dimension is twice that of the apertures 13 plus the thickness of two side walls 10.

Projecting from the bottom of the unit, that is to say, below the bottoms of the side walls 10, are six pegs of which four, designated 15, are located at the unit corners in alignment with the apertures 13 and the remaining two, designated 16, are located approximately midway along the length of the unit adjacent the side walls 10 in alignment with part of the apertures 14.

In cross-section the pegs 15 are square, their crosssectional dimensions being slightly smaller than those of the apertures 13, so that the pegs 15 are a comfortable fit into those apertures.

The two pegs 16 are of the same cross-sectional dimensions as the pegs 15. They are disposed on opposite sides of the central transverse plane of the unit 9, designated in FIG. 1 by the arrows l7, and are individually spaced from the plane 17 by the thickness of a side wall 10.

The box 9 including the side walls 10, the top 1], the gussets l2 and the pegs 15 and 16 is molded in a single piece from a robust plastics material such as polyurethane. The apertures 13, 14 may be as described provided by open ended holes formed through the top I], or they may be blind holes formed by holes in the top I] and underlying pockets. These pockets, if provided, are also integral with the remainder of the box 9.

FIG. 2 is an exploded view, showing part of scaffolding or a trestle formed from four of the units 9. Two units laid side-by-side on the ground are surmounted by two further units which are arranged one above the other and cross-wise to the lowermost units.

Because the length of each unit 9 is twice the unit width, the pegs 15 of the lower one of the cross-wise units fit into the apertures 13, 14 of half of each of the two lowermost units. The lower crosswise unit is accordingly supported by abutment of the bottoms of its side walls 10 with the tops 11 of the lowermost units. It will be noted that, because of the off setting of its pegs 16 to either side of its central transverse vertical plane, the lower crosswise unit has one peg 16 received in the appropriate half of an aperture 14 of one of the lowermost units (the left hand one as shown), while its other peg (not visible) is received in an aperture 13 of the other of the lowermost units.

The upper one of the crosswise units has its pegs l5, 16 received in the apertures l3, 14 of the lower crosswise unit, and is supported by abutment of the bottom of its side walls 10 with the top I] of the lower crosswise unit.

By adding units to one another generally in the manner described, scaffolding of a trestle adapted for any particular application can be readily built up. The units can be added to one another so as to overlap one another by half the unit length, either in side-by-side relation, or vertically in the manner of brickwork, or both. Horizontal location for each unit 9 is provided by engagement of its pegs 15, 16 with the sides of the apertures l3, 14 of the one or more underlying units 9 (if any). If pockets are provided below the apertures I3, 14 the pegs may also provide at least some of the support for the unit.

Each unit when laid provides an immediate platform for personnel, the top 11 being sufficiently rigid for that purpose.

It may be desirable for a unit 9 to be longer than it is wide by a integral factor greater than two; for exampie, it may be three times as long as it is wide. in such a unit four apertures 14 and four pegs 16 would be provided in two pairs each disposed a third of the length of the unit from the respective end.

In various modifications of the described embodiment the units 9 have apertures other than those described formed in their walls 10 and l l, and the bottom of the units 9 are closed instead of open.

In a further modification two pegs 16 are provided on each side of the unit, one on either side of the central transverse plane 17. They are spaced apart by a sufficient distance to accommodate the thickness of two of the side walls 10 between them.

In yet a further modification, shown in H6. 3, three apertures are formed in the top 11 of the unit in addition to the apertures 13 and 14. Of these additional apertures two, denoted by the reference numeral 30, are located at the ends of the unit and the other, referenced 31, is located at the very center of the unit. Like the aperture 31, the apertures 30 are centered on the central longitudinal plane through the unit. The dimensions of the apertures 30 are the same as those of the apertures 13, whereas the aperture 31 is square, its sides having a length equal to the dimension of the apertures 14 along the length of the unit. This arrangement provides for greater flexibility of assembly than the previously described arrangement because it enables adjacent units to be arranged in partially overlapping relationship across the width of the units as well as, or alternatively to, along their length.

I claim:

1. A building unit, for scaffolding or a trestle, comprising a hollow rectangular body having a length-towidth ratio which is an integer, and including a top forming a support platform and defining corner apertures at its corners and intermediate apertures at intervals of unit width along its length towards its edges with said intermediate apertures having a length in the longitudinal direction of said hollow rectangular body at least twice the corresponding length of said corner apertures, and a bottom having projections extending vertically downwardly therefrom, each projection in alignment with a respective aperture for engagement in the apertures of at least one other unit to locate said units in horizontal arrangement, the projections aligned with said intermediate apertures being offset from one another longitudinally of said hollow rectangular body so as to be disposed on either side of a transverse plane through said hollow rectangular body centrally of said intermediate apertures with which they are aligned.

2. A building unit, for scaffolding or a trestle, comprising a hollow rectangular body including a top portion and a bottom portion, one said portion defining four comer apertures and a plurality of intermediate apertures at intervals along the length of said hollow rectangular body at the edges thereof, with said intermediate apertures having a length in the longitudinal direction of said hollow rectangular body at least twice the corresponding length of said corner apertures, and the other said portion having projections extending vertically therefrom, each in alignment with a respective aperture defined by said one portion and with said projections aligned with said intermediate apertures defined by said one portion, and in corresponding positions towards opposite edges of said hollow rectangular body, being offset from one another longitudinally of said hollow rectangular body so as to be disposed on either side of a transverse plane through said hollow rectangular body centrally of said intermediate apertures with which they are aligned.

3. A unit as claimed in claim 2, wherein said apertures are defined by said top portion of said hollow rectangular body and said projections project from said bottom portion of said hollow rectangular body.

4. A unit as claimed in claim 3, wherein said hollow rectangular body has a length to width ratio which is an integer.

5. A unit as claimed in claim 4, wherein said intermediate apertures defined by said top portion are disposed at intervals of unit width along the length of said rectangular hollow body.

6. A unit as claimed in claim 5, wherein said top portion defines further apertures located midway across the width of said top portion and in transverse alignment with said corner apertures and said intermediate apertures. 

1. A building unit, for scaffolding or a trestle, comprising a hollow rectangular body having a length-to-width ratio which is an integer, and including a top forming a support platform and defining corner apertures at its corners and intermediate apertures at intervals of unit width along its length towards its edges with said intermediate apertures having a length in the longitudinal direction of said hollow rectangular body at least twice the corresponding length of said corner apertures, and a bottom having projections extending vertically downwardly therefrom, each projection in alignment with a respective aperture for engagement in the apertures of at least one other unit to locate said units in horizontal arrangement, the projections aligned with said intermediate apertures being offset from one another longitudinally of said hollow rectangular body so as to be disposed on either side of a transverse plane through said hollow rectangular body centrally of said intermediate apertures with which they are aligned.
 2. A building unit, for scaffolding or a trestle, comprising a hollow rectangular body including a top portion and a bottom portion, one said portion defining four corner apertures and a plurality of intermediate apertures at intervals along the length of said hollow rectangular body at the edges thereof, with said intermediate apertures having a length in the longitudinal direction of said hollow rectangular body at least twice the corresponding length of said corner apertures, and the other said portion having projections extending vertically therefrom, each in alignment with a respective aperture defined by said one portion and with said projections aligned with said intermediate apertures defined by said one portion, and in corresponding positions towards opposite edges of said hollow rectangular body, being offset from one another longitudinally of said hollow rectangular body so as to be disposed on either side of a transverse plane through said hollow rectangular body centrally of said intermediate apertures with which they are aligned.
 3. A unit as claimed in claim 2, wherein said apertures are defined by said top portion of said hollow rectangular body and said projections project from said bottom portion of said hollow rectangular body.
 4. A unit as claimed in claim 3, wherein said hollow rectangular body has a length to width ratio which is an integer.
 5. A unit as claimed in claim 4, wherein said intermediate apertures defined by said top portion are disposed at intervals of unit width along the length of said rectangular hollow body.
 6. A unit as claimed in claim 5, wherein said top portion defines further apertures located midway across the width of said top portion and in transverse alignment with said corner apertures and said intermediate aperturEs. 